1. Technical Field
The present invention relates to a paper feed device for an image forming apparatus that is disposed near an opening formed on a housing of the image forming apparatus.
2. Background Arts
A Patent Document 1 (Japanese Registered Utility Model No. 3129922) discloses a paper feed device that can prevent a paper jam.
The paper feed device disclosed in the Patent Document 1 is provided with a paper feed tray on which papers can be set from above. A transfer frame is fixedly provided along a downstream edge of the paper feed tray, and is provided with an opening opened toward an outside. The transfer frame is attached to a housing of an image forming apparatus, or is configured integrally with the housing.
In addition, a scraper roller is provided rotatably above the downstream edge of the paper feed tray. A drive shaft coupled with a drive motor is provided on a downstream side from the scraper rollers, and above a transfer start position of the transfer frame. The drive shaft extends longitudinally in a paper width direction, and is rotatable in a direction for feeding papers forward.
Further, a pick-up roller is attached to almost the center of the drive shaft along its longitudinal direction, and paper receive rollers having rigidity are also attached to the drive shaft on either side of the pick-up roller.
Here, a rotational force of the drive shaft rotated integrally with the pick-up roller is transferred to a shaft of the scraper roller via a gear mechanism.
In addition, a separation plate is provided beneath the pick-up roller so as to be opposing to the pick-up roller.
Further, a pair of secondary paper feed rollers is provided on a downstream side from the transfer frame so as to be viewed through the opening formed on the transfer frame.
In the above paper feed device, some upper papers among papers stacked on the paper feed tray are drawn forward by the scraper roller, and then only an uppermost paper of them is separated from other papers of them by the pick-up roller and the separation plate disposed on a downstream side from the scraper roller. The separated uppermost paper is transferred to the secondary feed rollers disposed on a downstream side from the transfer frame, and then the paper is transferred forward to an image forming unit of the image forming apparatus. Subsequently, images are formed on the paper transferred to the image forming unit.
During these processes, the paper receive rollers that have rigidity and are provided coaxially on either side of the pick-up roller attached to the drive shaft hold a warped paper and feed the paper forward together with the pick-up roller. Therefore, a warped paper can be prevented from jamming.